International Council for the Exploration of the Sea
MARICULTURE COMMITTEE by
K. Tiews 1980
BELGIUM
(G. Persoone and F. Redant)
Administrative Report
The two pilot-scale installations for mariculture, built at the Belgian coast in 1979 have been started up in 1980.
Research is in progress now to establish the cost-benefit of the operations on the basis of variation of a number of ~arameters which can be cl1anged within ti1e systems.
'rhe first .t=·ilo-c plant concerns the nursery-rearing of bivalves which is presently a bottle-neck in the controlled farming of molluccs 'rhe J.nboNttocy for Mariculture at the State University of Ghent, which in in charge of the researcn, joint1y with the Institute
for Murine Srientific Research (IZWO) is organizing an International Workshop on nnr:lery culturing, of bi·rc.lve molluscs in the framework of the COST Mariculture Action 46.
The Arternia res<:arch is talcen care of by the Arterni3. Reference Center at the Laboratory for Mariculture.
The Artemia pilot-plant at the Belgian coast is focusing on recycling agricultural waste products in protein biomass by intensive culturing of brine shrimp.
'I'he Artemie RefereJtce Center has been editing in 1980 a series of 3 books on "The Brine Shrimr' Artemia11 containing approximately 100 reviews and papers wl~.ich cover tr·.e wajo;-;:esearch areas on this partic'.llar crus-
t~cean URed worldwide in ~u1damental reeearch and in aquaculture.
'l' bl' ~:ut'opean M:H'.icnl t.Jre ~~or: i c.' l y, l he t•egi ::;tered office of which is located at the Institute for Marine Scientific Research in Belgium, has launched the 11World Conference on Aquaculture and International l\qJWcul t11re Trade Show" wl1' ::h Hi l i be convened in Venice, Italy in
l•lrm1,Pt· l•l!1'.
Statistical Information
There Has no culture of flat oysters (O. edulis) due to dyke construction in the vicinity of the beds,
CANADA
(J.E. Stewart and R. Driman) PACIFIC COAST Shell fi sh
A commercial spatfall of the Pacific Dyster (Crassostrea
~. was obtained in Pendrell Sound, the maJOr area of seed corlection. Production of oysters for both shucking and sale in shell, declined in 1981, due primarily to a reduction in seeding of beds in recent years.
A small private shellfish hatchery continued to operate in 1980 rearing largely ~~· The total amount of seed produced was minor.
The culture of the blue mussel, Mytilus edulis, largely on longlines, is still in the early developmental-pna5e.
A private commercial abalone (Haliotis kamschatkana) operation began production in 1980. The 1ntent 1s to breed this species and rear it to market size.
Fish
The federal experimental salmon fish farm programme has shown great success. Coho and Chinook 'commercial' rearing in marine cages show consistent survival of 70+ 5% to pan size.
Further rearing, to 2kg, results in losses of approximately 50%
from diatom (Chaetoceros) blooms, Bacterial Kidney Disease and Furunculosis, but still results in an economic gain.
The resources and facilities used for salmon rearing wi11 be utilized beginning in 1981 for an investigation of the
impoundment of herring to establish the potential application of such a technique in the production of roe, an important and economically attractive fisheries product in recent years.
Selective breeding studies utilizing rainbow traut in marine culture show great promise. A domesticated freshwater strain has shown excellent sea growth, exceeding that of salmon, but exhibits high (40%) mortalities at 120g. Survivors will be bred to develop a strain with lower losses. Strains reared from eggs imported from Norway and the U.K. are also being reared in this prograrnme.
A joint federal-provincial (British Columbia) study of the nutritional requirements of rainbow traut in seawater has begun. This incorporates the evaluationOfa number of dry and rnoist diets using a variety of perforrnance criteria and basic studies of nutritional requirernents, with the aim of producing practical diets for rainbow traut in seawater using Canadian cornponents.
Atlantic Coast Marine Plants
Two companies in Nova Scotia, have, for a number of years, carried out pilot studies on the culture of Irish moss
(Chondrus crispus). One recently terminated its studies whereas the other has expanded operations. In the recent past many biological stumbling blocks were surmounted and progress was being made in growing a east efficient product. This year the program was set back by a disease. The organism has been identified and steps are being taken to control it within the system.
The fisheries department of the province of Prince Edward Island is continuing growth studies of an unattached form of Chondrus crispus in various Island estuaries with the aim of developing an economically viable culture system.
In Newfoundland, an investigation of hatchery techniques for Saccorhiza is underway at the t~arine Sciences Research Laboratory of Memorial University.
Dyster (Crassostrea virginica)
A joint federal/provincial development project in northern New Brunswick continues to show great promise. Its goal is to increase production from private leases by improving
existing oyster culture technologies and transferring these to the private sector. Federal input in 1980 included monitoring of oyster larval populations and providing spatfall predictions to industry. This area produces two-thirds of the oysters landed in New Brunswick; over 90 metric tons from leased areas in 1979.
From the production history, the potential appears to be at least three times this and based on the area available for oyster culture could theoretically approach fifty times.
Final enhancements were made to the recently completed computer systems for Shellfish Lease Administration, and granting of shellfish leases for off-bottom mussel culture was i niti at ed.
Flat oyster (Ostrea edulis)
Interest in growing this species commercially on the Atlantic coast of Nova Scotia is substantial, following experi- mental and demonstration projects by the provincial government.
Hatchery rearing of sufficient seed to supp1y the initial pilot operations is planned for 1980.
The incidence of shell disease in this species in Nova Scotia has been surveyed. All year classes (1975-1979) were found to be infected, with an overall incidence of 10-20%.
However, in the relatively cool waters of this area, no seriously damaging effect was observed. An organism similar to Ostracoblabe implexa was isolated from shell lesions and is being maintained in culture. Its morphology, infectivity and physiology are being studied.
Blue Mussel (Mytilus edulis)
Commercial mussel culture using longlines is established in Prince Edward Island and Nova Scotia and promising exploratory operations are underway in New Brunswick. A
processing and distribution plant is planned for Prince Edward Island. With the establishment of firm market demand a number of new private ventures are in early development phases in the Maritimes and Newfoundland. Appropriate technology, particularly for overwintering in ice, is still a major need and experimental programmes to investigate this and other basic industry-oriented parameters are underway in all areas.
Sea Scallop (Placopecten magellanicus)
In Newfoundland, the Provincial Department of Fisheries has continued to support investigations into scallop culture. These included spatfall monitoring in Placentia Bay, Port au Port Bay and Bay of Islands. While spatfall in Garden Cove and Fox Island River reached near-record lev.els, extremely poor spatfall was recorded in the Bay of Islands.
Growth and survival of juvenile scallops at the new grow-out site of Spencer's Cove were monitored. Survival of l-year olds was well over 80%, a considerable improvement over that encountered in Garden Cove.
The transfer of culture technology to the private sector has begun. The Port au Port Development Association has started up a resource enhancement project at Fox Island River.
Funded largely by the Development Branch of the Provincial Depart- ment of Fisheries, the Asociation has set 2000 spat collectors.
Seeding of public grounds will commence in 1982 after accelerated off-bottom growth through the winter of 1981. A private
entrepeneur on the south coast of the island has also started up spat collecting operations.
A leasing policy has been developed to facilitate mariculture operations in the province.
Bay Scallop (Aequipecten irradians)
The second generation of this species, reared in quarantine from an original import by the Prince Edward Island Department of Fisheries, is being held pending their approval by federal authorities for transfer to Ca.nadian \'taters.
Growth in both F1 and F2 stocks showed considerable improvement over the previous year. In the closed system with severely limited water exchange growth rates comparable to those under natural conditions in the U.S.A. have been observed.
A chlamydia-like organism present in the original import from Connecticut has been detected in high numbers in subsequent generations but not in native species held in contact
with thern. Sirnilar, but doubtfully identical inclusions have been found in same native species both inshore and offshore. Investi- gations into the nature and potential threat from this organism and attempts to prevent its passage to subsequent generations are conti nu ing.
Lobster (Homarus americanus)
A three year pilot lobster culture study carried out under a federal contract with a private operator in Prince Edward Island wil1 be completed early in 1981. This was designed to develop and test commercially-applicable technology for rearing lobsters frorn canner to market size using eyestalk ablation and improved diets.
A rearing system has been developed using sea1vater from a shallow dr ill ed \vell. Thirty stocks of trays can house 8000 market lobsters individually. The system can operate on a flow through basis or on recirculation, and it has performed well under less than maximum loading, showing acceptable growth performance, disease control and energy efficiency. A number of formulations are under test to develop a feed that is palatable, easy and inexpensive to produce and gives acceptable production characteristics.
During the course of this work it was extended to include culture from egg to market. A number of options for larval culture regimes have beeo tested. A flow-through systen in rectangular tanks using brine shrimp nauplii as feed has shown best results. A stacked tray system is under test for juvenile culture and good progress has been made in feed development.
In federa l l aboratory stud i es, 1 obsters bil ater- ally eyestalk ablated averaged more than 300g at 13 months. At this age females had well developed ovaries showing a potential for a halving of the normal reproductive cycle in laboratory
culture, a phenomenon which could be of great significance in genetics research.
Sal mon
There are several areas in the southwestern Bay of Fundy area where climatic conditions are suitable for year- round cage culture of salmonids. In addition to the successful operation which began on Deer Island in 1978, there are new operations on nearby Grand Manan and Campobello Islands. The Deer Island site has suitably warm water (no lower than 0.2°C since 1978) which is not the case in Passamaquoddy Bay and most other mainland locations in the S.W. Bay of Fundy area. The successful operation at Deer Island and the promise shown by the other island operations has sparked interest in further development in the same general area. It is planned that up to 50,000 Atlantic salmon and 30,000 pink salmon smolts will be put in cages in 1981.
In 1980 the Atlantic salmon were smaller than those harvested in 1979. This size difference reflects smolt size which influences size through cage rearing up to harvesting and stock origin which determines incidence of early maturing (grilse) individuals. Salmon of comparable smolt size and of the same stock produced similar sized fish at harvest in 1979 and 1980. Of two stocks reared at Deer Island, one gave negligible ( l%) grilse after one sea year while the other stock yielded up to 70% of males and 30% of females as grilse.
Pink salmon were harvested at 2-3 lb after about 14 months of cage rearing. Most individuals were maturing when harvested and would not have been expected to grow any more.
These fish were not put in sea cages as early as possible (May- June) but were held in shore-based tanks until August. It is likely that a larger size at harvest would be achieved by putting the pink salmon in sea cages as soon as water reached 10° in early summer. A further trial with pink salmon is planned for 1981.
Sea ranching trials continued in 1980 with the release of 8,000 smolts at the Biological Station at St. Andrews N.B •• A delayed release (mid-July) was used to maximize return.
The smolts were reared from returns from an earlier sea ranching trial at the same site. Plans are being developed for a pilot commercial sea ranching trial during the next several years at Grand Manan. This location was chosen because of the lower number of herring weirs in the immediate area and the prospect of fewer smolts and returning adults being taken incidentally in the herring fishery.
A major component of the Salmon Genetics Research Program will involve genetic studies in support of commerical aquaculture. A joint study was begun in 1980 with the SGRP supplying 24,000 smolts of various stocks for rearing on the Deer Island site. Data on survival, growth and maturity are being collected as a basis for selective breeding studies to produce stocks of salmon with appropriate traits for sea ranching. Compari- sons of growth and maturity parameters are being made between cage reared and sea ranched individuals representing the same stocks.
These studies are also expected to produce genetics data with an application in cage rearing of salmon.
Physiological studies of growth and smolting are being conducted in support o~ cage rearing and sea ranching.
The thyroid hormone, triiodo-L-thyronine, has growth promoting effects and enhances salinity tolerance. This hormone is being used on an experimental basis to improve production of smolts by decreasing the time required and decreasing the cost of production.
Long-term laboratory and field experiments are underway to study possible environmental control of sexual maturation in cage reared Atlantic salmon. It appears that the pattern of maturation in a given salmon stock reared in sea cages differs from that as a result of sea ranching. Experiments are aimed at testing two hypotheses to explain the lower incidence of mature fish in sea cages in comparison with sea ranching. These concern low winter temperatures in sea cage conditions and the effect of diet.
Atlantic Salmon Nutrition
In the Halifax laboratory the effect of changes in dietary protein and lipid levP.ls in practical feed formulas on the performance of Atlantic salmon grown in fresh1.,rater at l5°C and 20°C, and in seawater at l5°C, was investigated.
A 16 week feeding trial using 12 dietary treat- ments (3 levels of protein and 4 levels of lipid) conducted at l5°C demonstrated that the dietary lipid level has a significant effect on protein utilization. Diet containing 16% lipid and 45 and 50% protein showed in1proved growth, feed conversi on and hi gher nutrient reserves in the body. The effect of high temperature (20°C) on protein and lipid utilization by Atlantic salmon was studied in a 10 week feeding trial. Results show that Atlantic salmon require a low lipid and protein diet at higher temperature due to increased utilization of carbohydrate for energy purposes.
The survival and performance of Atlantic Salmon Smolts fed dry diets (40, 45 and 50% protein and 9, 12.5 and 16%
lipid and their combinations), oregon moist diet and purified diet was evaluated under laboratory condition in sea water. Fish fed a pelleted diet containing 16% lipid and 45% protein showed similar growth, flavour and texture properties to those fed oregon moist type diet. Dry feed showed better feed conversion than moist diet.
Rainbow Trout
In Newfoundland commercial production in 1980 was from a brackish embayment. Trials in full seawater showed very low mortality and will be expanded in 1981. A production of 30 MT annually is projected for this operation.
The major producer in the region, growing rainbow trout in cages in the brackish waters of the Bras d•or Lakes in Cape Breton, Nova Scotia, overwintered commercial quantities of fish which were successfully marketed smoked at a size much larger than the former pan-sized product.
At this site returns of escaped fish are substantial and suggest a potential for sea-ranching as a commercial technique. Fish have been tagged and released to provide data for assessment.
Tuna
As in 1979, the numbers of fish caught in St.
Margarets Bay for impoundment and fattening for fall slaughter was belo1.,r expectations. A weak market in Japan resulted in lowered prices. Unusual numbers of small fish, less than 100 kg were caught, and released and the proportion of females in the impounded animals was observed to be approximately double that
pre~iously recorded.
PACIFIC COAST
Dyster (Crassostrea ~)
Seed on shell (Vert i ca l culture) Mark et (shucked)
Market (in shell) Musse l (Mytilus edulis) Pacific Salmon Species
ATLANTIC COAST
*Dyster (Crassostrea virginica) Musse l ( Myt i l us ed u l is)
Rainbow trout (cages) Atlantic salmon Pink salmon Tuna
*Preliminary estimate
METRIC TONS -
2,007 - 3.6
l ' l 03 36.3 83.0 3.5 2.8 29.7
NU MB ER 258 X 10 6
357,600
-
Not available
$US(OOO's}
l' 04 7
l '020 3.7
890 32 260 17 6 110
l OJ
.PENMARK (E. Hoffmann)
The experimental work with turbot (Scophthalmus maximus) and pacific oyster (Crassostrea ~) has continued in l98o.at two small research farms, situated at the power plants, Asnæs, northwest of Copenhagen and Skærbæk in southern Jutland. The oyster pro- duction has given very promissing results and a production in commercial size is planned for 198o.
The number of culture beds for blue mussel (Mytilus edulis) has increased and the interest for this species is expanding.
In the Limfjord area 2 raise in the production of the flat oyster (Ostrea edulis) is wanted. The building of a hatchery is under consideration. The total production in the Limfjord in l98o was only 15o.ooo individuals.
Production of rainbow traut (Salmo gairdneri) has increased slightly to approximately 300 tons. - Most fishes were between l 1/2 and 2 l/2 kilos.
Statistical information Flat oyster (O. edulis) from culture beds -
Rainbow trout in enclosures, less than 0.5 kg each Rainbow trout in enclosures, more than 0.5 kg each
*)rough estimates
Tonnes
83 224
No.(in 100 000) Valne ( inlOOO US . .Z)
150 180*
125*
650*
FINLAND (P. Tuunainen)
Mariculture in Finland is based on one hand on sea ranching of salmon (Salmo salar), sea-traut (Salmo trutta trutta)and migratory whitefisb (Coregonus lavaretus)by introducing smolts of salmonids and 1-summer old whitefish young into the sea. On the otber band it is based on production of rainbow traut (Salmo gairdneri) in net cages and enclosures for human consumption. Mariculture pro- duction is continually increasing. This is caused by good domestic markets for rainbow traut and by efforts to increase the volume of sea ranching of the species mentioned above. In 1980 a new fish farm was constructed in connection with Olkiluoto nuclear power plant, western coast of Finland, to produce salmon smolts for introductions into the Baltic Sea.
Except fish farming restoration of salmon and sea-traut rivers is going on and remarkable increases in the numbers of parrs in the restored rapids have been reported. In one of the rivers, Simojoki, flowing into the Gulf of Bothnia constant monitoring program is going on.
Study programs were also carried out to find out the production biological and economic results of the introductions for sea ranching,to improve the quality of reared fish young, to measure the quality by physiological testa and by tagging the fish. Work has also been done to improve the fish feeds, rearing methods and to decrease water pollution caused by larger fish farms.
Statistical information (for 1979 only as figures for 1980 not yet available)
Tonnes No. (in 100 000)
Rainbow trout in enclosures, more than 0.5 kg each 794 Salmon, for introductions,
l l 2.78
2 years and older
Sea trout, for introductions, 40
7.78 2 summers old and older
Migratory whitefish,for
80 81.49
introductions, l su~mer eld
Value (in-y-QQo US.Z)
3 600 500 l 000 600
FRANCE
(J. ADllOUU et Mo GUILUUO)
Peotinidl• (ooquilleø St Jaoquee et petonoleø)
~ ~ a Loe NM! l de o• tap Ile &WIIt pOlU'IIui Y.h o We de S&int :Br:Lwo, en Bade de Brut ot an :Bretagno Sud. in r&it~on dtuu -.unJ.uø oonditionø h,ydrolo- giqueø et de la diminution du øtook de genitourø danø oeø diffe~entea soneø, leø resul- tats ont toujoura
't'
faiblea ( 5 a 40 par oolleotour ). Deø eaøaiø d'elevage en eoloae- rie ont ed lllen4a au CBEIO - OOB et a la SA 'IVAR. lb ,,1ont fourni une quanti te lim.i Ue de naiøø&ilhChlamocø varia r La oolleote du naiøøain a ete tentee
a
nouveau en Rada de Brest et en Baie de Quiberon. Deø øemiea
partir du naiøøain oapte en 1979 ont ete reali- t~es et auivis en Rade de Brest (Comite Looal des Piches Maritimes, en oollaboration avec l1equipe piohe CN&XO- COB). Des øemiø ont egale~~ent ete faitø dans les Pertuiø charentaiø (I.S.T.P.M. - Comitea looaux dau Piohea Maritilllea).Veneridtq ( palourdeø )
Les easaiø d 1 tHevage en øol des palourdeø, principalemEmt de la palourde ja- ponaiøe Rudi tiJ)ØB philippin&rUI!! ont ete etendUIIil d&nlll lø cadre d 1un progrme national. Ill sont suiviø par le CNEXO/COB et par lea laboratoires I.s.T.P.M. de La Trinite Sur Mør, Nantes, La Tr&~~blade et Aroaohon. A oe jour, le1 r~øultate ont ete exploites øurtout en Charente Maritill18 grioe
a
l'aotion de l'ADACO ( Aøøooiation pour le d~veloppement da l'A- quaculture dans le Centre Oueøt ). D&na oette region, quatre nurø6rieæ øont operationnel- leø et unø oinquanWne d 1 exploi tanta u livrent dha
preunta
la oul ture de la palourde.La produotion oommencera
a
itre øignifioative en 1981.lialiotid&e ( orm.aux) ( CNEXO - COB )
L'eoloøerie d'Argenton a desormais pour objøctif l1optimiøation de øeø teoh- niqueø.
in 1980, la production de juveniles a
ete
porteea
5 OOO/m2de
o a
6 moia et de 6a
12 moiøa
4 8oo/m2• De oe fait dana øa forme actuelle 11ecloøerie a produit 115 000 animaux d'un ana
partir d'une ponte donn•• ' oomme les inøtallations lont oonoues pour ao-cueillir lea produits d'une ponte tous les 6 meis, la capacite theorique de l'unite de production experimentale d'Argenton peut atteindre 200 000 juveniles d'un an.
Au titre du grossiasement dans la zone intertidale, la mise en place d'habitats artificiels permet d'esperer en 1981 un taux de recapture de 40% sur des habitata prototypes mis en oeuvre en 1978 et en 1982 de 60% aur des habitats de types industriels immerges en 1980. Ce dernier taux de recapture devrait assurer la rentabili- te de l'elevage.
Ostreidae (huitrea)
Ostrea edulis : La regression de la maladie due
a
Marteilia refringens eat confirmee. Le paraaite eat toujours present dans le Golfe du Morbihan, les rivieres d'Au- ray et de Penerf et dans la Rade de Brest. Dans ce dernier secteur, lea huitres naturellea, semblent s'3tre immuniaees. Leur croissance, leur qualite et les mortalitea sont normales.L'epizootie due au nouveau protiste X, nomme Bonamia ostreae, s'est deve- loppee dans toua les centres d'elevage bretons. Des mortalitea importantea (50
a
80 %)ont ete conatateea ~ur les huitres ågees de 3 ans et 4 ans. Ce parasite a egal~ment ete decele sur des huitres elevees
a
Arcachon et dans le bassin de Marennes-Oleron.Mytilicola ap. et Minchinia armoricana ont ete signal(·.
La production de naissain eat evaluee
a
450 T. Le atock de 18 mois (hui- tres de demi-elevage)a
2 000 T. La production d'huitresa
la consommation E'est situee au- tour de 5 000 T.Crassostrea gigas
Mytilicola orientalis s1est etendu
a
de nombreUX centres d'eleVaRe situes aur la fa9ade atlantique. Les pourcentages d'huitres paraaitees et les taux d'infestation sont tres variables. Ila n'excedent cependant pas )O% pour un taux maximal de 5 ~·tilicolapar huitre.
Des etudes sont realiseea sur le "chambrage" avec production de ,;rel. La carence de certaina acides amines pourrait etre
a
l'origine du phenomene. D'ur~e fa9on plus generale1 la qualite de la coquille (forme et structure), se degrade dana de nombreuses ~ones. L'influence du milieu semble preponderante dans le proceasua.
La production globale
a
la consommation (70 000a
Bo 000 Tonnes) eat en baisse par rapport aux anneea precedentea (100 000 •rennes). Cette tendance resulte des mau- vais resultats de captage de 1978, en particulier dana le bassin d'Arcachon.En 1980 des fixationa importantes ont ete obaervees dans le bassin de Marennes-Qleron. Le captage
a
Arcachon ne devrait pas satisfaire la demande de ce bassin.La production en demi-elevage, dans ce dernier eat en augmentation par rapport
a
1979 ; il atteindrait 350 Tonnes.HYtilid&e (.aule~)
MOCtilus edulis Les travaux sur leu phenom~neø d'envasement et sur la rechørohe de methodeø de "devaøage" sont pourauivia. La oraie a
ete
testee avec quelqueø suooeø aur une vaøiere øituee en amont du baøain d'Arcaobon.La produotion ~tilioole fr&nQaiae evolue autour de 50 000 Tonnea, le
pre~er bassin producteur etant oelui du Viviers-øur-Mer avec une quantite d~ 10 000 Tonnes de mouleø de bouohotø. Lea methodeø d'evaluation des øtooks, propree au bassin de Thau (oul- ture en ~uspenøion sous radeau) ont permil d'4valuer la bioæaaøe
a
7 000 Tonnes.--- - ---- - - - ---
Des reoherohes aur les possibiliteø de culture d'Euchema spinosum ont 6te entreprises aux Antilles tranvaiseø (r.s.T.P.W.). Deux moduleø øemi-induøtriels de 2 500m2
chaoun ant ~te installea, l'un ~n M&rtiniqu~
9
l'autre en Guadeloupe. Les reaultat1 obtenus ontete
exoøllentø au premier l&meøtre9 moina bona par la suite en raiaon deø de- gate oapaøionnes par le cyolone Allen. Le grand module de Guadeloupe, detruit en Dacembre par une oause inconnue a da ltre entierement reconatruit.Une etude et des eøaais de oultur~ de l'algue comaatible Undaria pinnatifida ont ete oommenceø dana l'etang de Thau. Cette espece introduite en 1971 lors da l'importa- tion de naisøain da Craasostrea a etendu progressivement son aire de rapartition sur tout le para oonohylioole de oe aecteur.
Crustaoes
~ ' La production da post-larvea dal acloseries a ete la auivante en 1980 ' Ebloserie d~ 11Ile d'Yeu (I.s.T.P.M.) : Pluø de 180 000 poat-larves et 10 000 juvenilef Eeloserie d'Houat (APASU!Q r 100 000 post-larvea et 10 000 juveniles
L'etude comparative de la oroissance en oaptivite du homard european, du homard ameri- oain et døs hybrideø ø1eøt pourøuivi• (I.S.T.P.M.). Le comportement dea jeuneø homards •n semi-liberte a ete 'tudi6 aux Vivierg du Porello (AP~).
• C!.i~'Y_li'!_'!_§.'§. (Penaeus sp. )
Des essais de controle de la maturite sexuelle conduits anterieurement sur
~enaeus japonicus ont ete etendus a d'autres especes : Penaeus stylirostris et Penaeus vannamei.
Des etudes a caractere fondamental ont ete entreprises sur le role de la glande androgene dans les processus de reproduction. , 1 ~ •
Sur un plan plus applique, des recherches ont ete entrepr1ses en vue ~ ~el1orer la stabilite de l'aliment, de diminuer le lessivage des elements nutr1t1fs et d'arneliorer les resultats globaux d'elevage par distribution automatique et con- tinue de l'aliment durant la nuit.
Poissons
Loupes, dorades et bars: Une etude de la croissance de ces poissons a ete commencee en 1980 en Martinique (I.S.T.P.M.). La courbe de croissance est superieure
a
celle constatee en Metropole.SALMONIDES
Des recherches ont ete effectuees sur 4 especes : Oncorhynchus kisutch~ Salmo
salar~ Salmo gairdneri et Salmo trutta, tant pendant l'elevage en eau douce que pendant l'elevage en eau salee.
Sur Oncorhynchus kisutch, on a tente de rechercher si les causes de la mauvaise reproduction de femelles maintenues en captivite en mer etaient d'ordre nutri- tionnel.
Les resultats definitifs ne sont pas encore connus, mais les perforrnances sont mediocres. En eau douce, toutefois, de bien meilleures pontes ont ete obtenues.
Sur Salmo salar, une etude des criteres physiologiques de la smoltification (Na K ATPase) a montre que les resultats obtenus chez le saurnon coho etaient transposables a Salmo salar, de meme poids.
Chez Salmo trutta, deux souches ont ete etudiees. L'une ne smoltifie pas, l'autre presente un debut de smoltification. Cette derniere supporte bien la vie en mer
(meme durant l'ete) et s'y reproduit bien.
Sur Salmo gai1•dneri, l' etude des meilleures conditions de trans fert en mer (taille, epoque de l'annee) a ete poursuivie.
POISSONS MARINS
~ §.Qff (Solea vulgaris)
Plus de 10.000 juveniles de 3 mois ont ete e eves et ut1lises pour des expe-~ ~ ~l ~ · ri~nces sur_l'elevage de transition (3- 12 mois). Pendant le "sevrage", les me1lleurs resultats sont obtenus grace a l'emploi d' l' t d
stab.le dans l'eau. Au dela- du sevrage, les . a 1men s onnant un gel me1lleurs taux de survie et la c;olss~nce la flus rapide ont ete observes sur des lots nourris de pate forrnee d un melange d aliment complet et de chair de mollusque.
=
'!.!!.!!.!!.rj_T_ (Scophthalmus maximus)Dur~n~ la phase initiale de l' eJ.evage, deux causes de rnortalite ont ete mi ses en.e~~Jence : l'u~e. est rl'ordrc microhien, l'autre d'ordre nutritionnel. En ut~~1s.1n~ d~s rottfL·res.c~nml~ "capsulL'S vivanles", et plus specialement en le_
fal sant lngerer des antlb7otlque-, et des nutriments' on a pu ameliorer tres ur nettement les taux de cro1ssance et de survie a l'age de 2 mais. -
GERMAN DEMOCRATIC REPUBLIC (W. Laos)
In 1980 mariculture research was continued according to research and development programma. The activities were concentrated on the following main points:
1. The co1nmercial production of rainbow traut fingerlings in brackish water based on the results of the large-scala experiment in 1~7~ was initiated. The main data of the large- scala experiment were reached.
2. Concerning rearing fry of rainbow traut in heated brackish water valuaule resultG were obtained from small-scala experi- ments aiming at shortening of the production cyclee Studies are continued.
). Rearing work on a rainbow traut stock resistent against diseases in brackish water has been pursued successfully.
Measures have been initiated to extend brood stock facilities for further experiments.
4.
Large-scale tests on oral immunization of rainbow traut against Vibriosis could not be carried out in full scale. The positive impact of Vibriovaccine was repeated in several laboratory experiments ..5. Studies on adaptibility and tolerance of Hypoihthalmichthts molitrix and Aristichthys nobilis x Hypophtha michthys mo itrix to brackish water were finished. Together wLth the results obtained in 1979 there is now a good basis to evaluate salinity and temperature conditions for rearing of juvenile age groups of above mentioned specieso Small-scala experiments on rearing fry in heated brackish water have been continued.
6. Engineering work was concentrated on
- drafting a pilot-project for utilization of heated brackish water of a power station•
- studies to promote projects of utilization of coastal waters for mariculture considering the present state of engineering.
The resulting short-term programm is aiming at developing effective cage culture technologies under given conditions.
S'l'A'l'IS'l'ICAL Il~FORIVIATIOH ON MARICULTURE PRODUCTION GDR Species
hainbow traut in euclosures - less than 0,5 kg each - more than 0,5 kg each
tonn es appr. _j_Q 410
total 420
Crassostrea giqas:
FEDERAL REPUBLIC OF GERMANY (K. Tiews)
Indoor experiments on the reproduction and rearing of spat were continued as well as outdoor experiments on the fattening of spat to marketable sizes. The construction of the experimental station Langballigau near Flensburg of the Institut flir Klisten- und Binnenfischerei was completed. 25,000 spat were produced.
Container culture experiments on various places along the German North Sea and Baltic coasts were also continued by the Institut flir Klisten- und Binnenfischerei.
Growth rates of spat fed on algae (Nannochloris) diets from phytoplankton cultures are studied under different environmental conditions at the Institut flir Meereskunde, Kiel. The aim is to find methods for a routine production of seed oysters.
Rainbow traut:
Techniques for sea cage rearing are developed at the Institut flir Meereskunde, Kiel as well as feeding strategies with different diets. The stress which intense cage rearing causes to the
surrounding natural environment is investigated. A pilot plant for traut production in silos supplied with brackish water from the cooling system of a power plant is accompanied scientifically.
The possibility of sea ranching with 4 to lO weeks old juveniles early weaned to brackish water of 16 °/oo S shall be tested.
The gas-physiology and energetics of traut respiration against several environmental factors is studied under the aspects of optimal growth and production rates.
Cage farming experiments:
Cage farming experiments with rainbow trouts were carried out off the coast of Heiligenhafen, of Langballigau and of Eckernforde by the Institut flir Kusten- und Binnenfischerei.
Salmon:
Methods for fry production in Germany and sea water cage rearing techn1ques are under investigation.
~~~~2~~~~~
Fry rearing ln cages with underwater lights to use the natural zooplankton resource of a lake is tested under quantitative aspects. The 6 months old fry is used for a sea ranching project in a brackish water fjord.
Turbot:
Mass production of fingerlings. The concept is to rear the larvae with high survival rates on a diet of natural plankton for which cultivation methods are worked out. On the base of plankton algae cultures rotifers and copepods, mainly the species Eurytemora affinis are produced. Regarding the latter most biological obstacles have to overcome.
Eel:
Research on eel farming in heated effluents of a conventional power station was continued at the experimental station Emden of the Institut flir Klisten- und Binnenfischerei. Also scaling up experiments for the mass rearing of elvers in silos
including the optimisation of feeds for these was continued by the same institute in its laboratories in Hamburg.
Fish nutrition:
Work was continued on the development of fish feeds for rainbow trouts in which fishmeal as protein source was substituted by other conventional and unconventional protein sources (Institut flir Klisten- und Binnenfischerei) . Also the development of eel feeds was continued by the same institute.
Recirculation sea water systems:
The biological station of Helgoland concentrated work o~ the
optiinisation of water quality management in brackish water recycling system, investigations on combined biological-chemical w~ ~r
treatment in intensive fish culture units. Also the Institut flir Klisten- und Binnenfischerei continued its work on the development of a recirculating sea water system.
Fish pathology:
Work to develop methods with which to describe stress conditions for fish in intensive aquaculture systems was continued at the Institut flir Hydrobiologie und Fischereiwissenschaft of the University of Hamburg.
Physiology:
Cryopreservation experiments on long-terme storage of sexual products of economically important species were continued at the Biologische Anstalt Helgoland.
Statistics (Federal Republic of Germany)
Spe eies
Blue mussels (Mytilus edulis) Pacific oyster (Crassostrea
~ from vertical cultures Pacific oyster (Crassostrea
~)seed laboratory reared Rainbow trout in enclosures less than 0.5 kg each Eel (Anguilla anguilla)
not fresh water
Tonnes Approx.No.
in 100 000 11 100
2.1 2 4
8
Value in 1,000 U.S.Dollar
2 200 7
11 14 60
JCELAND
(I. J6hannesson and s. Einarsson)
ill!• tltt.<JJt la.J'rning .i.r1 :;•'d \vd1<.::t .111- t.i 1 r,,J: Lite.'
·>:j•<C:t'illwnl
:lll • J h'l' i '/.-l t t'~
1vi t lJ s.t l Ht<;IJ
:'od lntc'It
Titt:' l'ishecie::; Ac_,so'--·iation ltdc; finic;tteJ tht:it·
tdr·ming in net pt:ns at Hafnir on Reykjanes t'Itt t;r·j·Pi se:_; ltcJV<: starL,:::d pruduction there. ExpePimcnts Jc~t•ming irt r;rindavik (on I<eykjanes), where warm se<~ Wd1er l 1 ., 1111 d r·i llltu.Lt• is }!llffil""d i ntu tanks si:anding on the shor•e is sti l l
:<,1,1 ,j li).; ,_,fl.
'l'ltt:> Fi~:lt..:J·ies P.::;suL·i..~t ion has in past years conducted experi- lllt...,ril:-o lviilt Sdlln•.)n tarming in estuary Lake Lon in North Iceland.
i']tt_•:.c,·2 '-"xpet•jJlll'l1ls \•liLl he culltinued.
l'I'iv-1Le erttc~cj.Jr·jse, Iungulax Ltd. cllld the NoPwegian salmon
1 .tl'Jlli n1~ c:t;JttjJdltY l•luvl i. have entered into co-operation. These cornpan.ies
1vi Il ••,ctt'l'V colt! trials witlt salmon f:n·ming in the sea and ocean t',J!Jt..:Li.Jt/".
A p11l.JI it .·Jltctt·eltoldct'S, FisLeldi Ltd. have s1a.l'ted tlteir smc.Jt l~'l'i. ·d 11 ('l i ()J l .
l'wu lllc.ll ·e ·~'(,fJJ},cliJ j c<: hl l Jr Lo:--: Lid. and 1-iola.la.x Ltd. have a_; su
Sl,JJ'[c-Li l]tc'.i1' SJ!t(>J1 pt•,)d<J• ilufl.
NETHERLANDS (M. Fond)
The private enterprises for cornrnercial culture of Rainbowtrout in seawater are continued, with a reasoble hope for success in 1981.
In the Netherlands Institute for Sea Research on Texel a research project was started in 198J on the development of a dry food for culture of Sole
(~ solea). The work is carrled out as a joint venture of three partners:
the Netherlands Institute for Sea Research ,the Fishcul ture department of the Agricultural University Wageningen1 and the research department of a private fi tih fu od fi rn,.
INTRODUCTION
NORWAY (G. Naevdal)
Research on problems related to mariculture is carried out by the following institutions in Norway:
l. Section of Aquaculture, Institute of Marine Research, Directorate of Fisheries, Bergen (including two research stations, Matre Bnd Austevoll)
2. Institute of Vitamin Research, Directorate of Fisheries,Bergen 3. The State Biological Station, FlØdevigen, Arendal
4. Research Station for Salmonids, Sunndalsøra and Averøya, Agricultural University of Norway
5. Institute of Fisheries Biology, University of Bergen 6. Institute of Fisheries, University of Tromsø
7. Regional High School, Sogndal
In the following report these institutions are referred to by number. (l) and (4) have continued their long term experi- ments on salmonids in 1980. The other institutions are main-
ly concerned with short-term experiments both on salmonids and on new potensial species for aquaculture.
RESEARCH PROJECTS Gene ties
Experiments with seleotive breeding of Atlantic salmon and rainbow trout were continued at (l) and (4). The following sub-projects are included,
a. Selection program to increase growth rate, (l) and (4), reduce mortality (4) and improve meat quality (4).
b. Study of phenotypic and genetic parameters in production ta i ts ; (l) and ( 4) .
c. St'.Jdy on inbreeding depressionJ (4) d. Study of heterosis effect1 (4)
e. Induce polyploid to obtain steril fish 1 ( 4) f. Induce gynogenesis (4).
- - - - -
A project concerning antipredator behaviour in Atlantic salmon smolts was started (l). The behaviour of cultivated smolts in relation to potential fish predators (saithe, traut and pollac~ was observed in a pond in order to find out possible differences in smdlt reactions to predators. Later on will be tried conditioning of smolts to avoid predators in an effort to improve recapture of released smolts.
Physiology and nutrition
Laboratory experiments of nutrition, digestion,growth, meta- bolism and energy budget of cod have continued (l). Also studies on the effect of smolt size on subsequent growth rate and age at sexual maturation, and changes in the renin-angio- tension-system during smoltification in Atlantic salmen have been continued (l). The experiments with feeding of salmonid fry with steroids to obtain sterile or unisexual fish were considerably expanded (l).
Use of Calanus for pigmentation of salmonids was further tried out (l), and sa was use of shrimp wastes for salmonid feeding.
Acidified feeds treated with hydrochloric, formic or sulphuric acid were fed to rainbow traut to test the effects on protease activities, growth and feed utilization (2). Silage conservation of fish feed, including shrimp wastes, was also studied by (l) and (4). Studies on protein, fat and carbohydrate in fish food, digestability, feed consumption at different temperatures and of varying fish sizes, and comparisons of wet and dry diets in salt water at low temperatures were carried out by (4).
Experiments on lipoid liver degradation due to lack of Vitamin E (l) and studies on egg quality of reared farmed salmonids have been initiated (4).
Use of binders in salmonid feeds (to increase feed efficiency and reduce water pollution) was studied by (2). About 30 different available products were tested for consistency and degree of decomposition in water. Of these, ten was further studied with regard to digestability and effect on growth rate of trout.
Pathology
In 1980 the work (l) on diseases in mariculture has mainly been concentrated on vaccination against vibriosis. Compara- tive studies on different types of vaccines and vaccination methods were carried out. Spreading of IPN-virus in the marine environment around fish farms was also studied.
Aquaculture technology
Experiments to assess the effectivenes of several antifouling impregnants for net pens and rearing tanks were continued and expanded in 1980 (l}.
Storage of live saithe in net pens for subsequent delivering to the fishing industry was studied (l) also in 1980. Especially the effect of handling and thowing were paid attention to
this year.
Studies of resirculation of fresh water for smolt production were carried out at (l) and (4). Oxygen consumption and ef-
feet of varying oxygene levels as well as effect of super- saturation with nitrogen were studied at (4).
Raising of smolt in net pens in freshwater and use of submerged cages for fish farming in the sea were studied by (l) . Treat- ment of acid water for smolt production was also paid attention to (l).
Rearing of marine fish larvae
Experiments on hatching and rearing marine fish larvae and fry in land situated basins (3), plastic bags in the sea (l) and a closed poll (5) were continued. In plastic bags and the poll cod larvae were reared, while in the land basin rearing of larvae of halibut and turbot was tried. Natural food was used in these experiments.
Other projects
Experiments on commercial culture of mussels, Mytilus edulis, were continued1 (l) and ( 7) 1 and similar experiments on growing oysters and scallops were initiated (l), (6) and (7). Con- cerning oysters especially possible positive effect on growth rate of raising oysters in the vicinity of fish farms was paid attention to.
At (6} the investigations of the possibility for culture of anadromous Artic charr, Salvelinus alpinus, both in fresh- water and in sea cages, were continued. These investigations include hatching and first food uptake, osmoregulation and the effect of environmental factors as light and stocking density on growth rate.
STATISTICS
Quantities of salmonids produced are given in the
table below. The main mariculture production in Norway still is rainbow traut and Atlantic salmon" The public statistics give no breakdown on production in fresh and salt water, and the production in fresh water is not reported in the inland fisheries statistics. Thus the total production is given in the table below. However, the quantities produced in fresh water is small, and 2-3% of the total production is indicated.
Concerning other species, no statistics exist, but small quanti- ties of blue mussels and oysters were produced.
Statistical information
Tonnes Value in l 000 us . .z Rainbow trout in
enclosures, more
than 0.5 kg each 3 360 12 782
Salmon in enclosures 4 153 34 982
POL AND (B. Lubieniecki)
Further studies of rainbow trout farming in cages in brackish water were continued during the year of 1980 with special emphasis to the overcoming and preventing septicemia diseases.
Treatment with su1phonamide was app1ied,
Injective vaccine against Vibrio produced in the German Democratic Republic and hyperosmotic vaccine made in the USA were tested. The first experiments with the tagging of rainbow trout acclimatised in cages during winter time were undertaken.
Statistica1 information
20 tonnes of rainbow trout, more than 0.5 kg,each were produced.
Sprimp Culture
PORTUGAL (J.C, de Ataide)
Experiments on Palaemon serratus culture have been undertaken. The incubation period of the eggs was followed and determined at different temperatures in order to induce a great number of fema1es to spawn simultaneous1y for mass rearing purposes.
Mass rearing experiments of the 1arvae be1onging to two different populations of the Portuguese coast, one from the south coast and the other from the northern part of the west coast were started late in 1980 and are to be continued this year. Different concentrations at different food 1evels are being tried.
Lobster Culture
Experiments on Nephrops norvegicus cu1ture have been undertaken, Successive embryonic stages have been submitted to artificia1 incubation and the period up to hatching was fo11owed. The experiments are to be continued in 1981.
SWEDEN (B. Holmberg)
LccoL'ding to Swedish Water Law about 2 millions of reared salmon smolts had to be stocked every year in the Baltic to compoH:sate for destroyed natural reproduktion. Addi tionally 600 000 salmon and sea trout smolts have been stocked succes- fully in coastal waters to enhance the stocks aimed for commercial as well as sportfisheries. Short mi.grating strains of sea trout have been tested in certain areas. Experimental tests vrere made to control the effect of smolt sice and time of re lease to increase the survi val rate of smolt vri th the ultimate purpose to increase the yield in the fisheries.
Commercial farming of rainbow trout in fish pens from spring until autumn in coastal areas has increased since last year.
Culture of rainbow trout all the year around has been tested by some forms in the Baltic in order to produce fish of bigger sice. On the west coast in higher salinities, ex- periments have been made to overcome the problems to cultivate fish in the cri tical temperature interval ( -0.5 to l. 5uC) . Vibrio:;i:;
was common in the farms located in brackish and seawater.
The cormnercial farming of blue mussel has increased during the last years on the west coast of Sweden. A production technique vri th lines and buoys has been adapted to S1·redish conditions. The ecological effect of such cultivation on the bottom sediment and surrounding waters are studied.
An investigation about future prospects for aquaculture in Sweden was started 1979 to look into differen·t areas of this field (biology, technology, economy and marketing aspects).
A report in 1980 included proposals for future planning of aquaculture and the need for it in Sweden.
UNITED KINGDOM SCOTLAND (A.L.S. Munro)
At present all comrnercial mariculture aotivitiee are located on the west coast of Scotland.
Fin Fish:
Atlantic salmon (Salmo ~) Salmon farming is the biggest mariculture industry in Scotland and is still growing at a significant pace. Five new sea oage sites were recorded in 1980 adding to the 17 already in operation of which 14 have only begun operating in the last 5 years. The tonnage of salmon produced wa.s 598 tons compared to 520 tons last year a somewhat disappointing figure in relation to the other signs of growth. A bacterial disease, furunculosis, was a signifioant factor contributing to low production in 1980.
The number of ealmon emolts placed in sea water was 1 418 000 compared·to 834 000 in 1979• From the 1980 smolts it is estimated produotion of salmon should be 1 700-2 500tons in 1982 (and from the 1979 smolts 1 000-1 500tons in 1981) with additional amounts for grilse tonnage to be added.
The technical problems facing salmon farming have been considerable. Significant losses of smolts have occurred in their first sea year (1D-4Q%) from a variety of causes including, predation, storm damage, escape and disease. Maturation as grilse also accounts for approximately 3o% of fish after the first sea year.
However the industry with help from public funded research is developing solutions to many of its problems.
Rainbow trout (~ gairdnerii) Some 6 sea cage sites produced 86 tons of trout in sea or brackish water, a slight drop in production from the previous year.
Sea oage farming is best suiteu for produoing larger than pan sized fish yet a signifioant market remains to be found for this size of fish. Produoing table size fish in seawater given that transfer must be at 70-100 g to aohieve good survival in full salinity sites is apparently of limited profitability. Competition for good sea oage sites with salmon farming is another faotor depressing growth in this seotor.
~ (Anguilla anguilla) Some 15 tons of eels were produoed in seawater using heat from a nuolear power station. This figure should be inoreased several fold in 1981 based on a greatly inoreased tank oapaoity now installed.
~ (Soophthalmus ~) Total produotion of 15 tons was recorded at two sites using heat from a nuolear power station. Some increase in production is to be achieved from a new pilot soale demonstration unit built by the White Fish Authority. Survival of early juvenile stages still poses problems whioh limit the growth of production.
~ Experimental quantities of Dover sole(~~) and sea bass (Dicentrarchus ~) were produoed in heated sea water.
Moll us es
Oysters (Crassostrea iaponioa and~~) Estimated production was
200 OOOJapanese and20 000 nat1ve oysters from 9 farms. The growth of the industry has been limi ted b,y laok of looal demand, the principal out le-t for oonsumption.
A single hat c he ry produoes sufficient se ed for all looal demand wi th most of its pr~iuction of both species being sold for export. The long period of growth to market size especially for the native oyster is another faotor limiting the industry•s growth.
~ (Mytilus ~) Estimated production was 40 tons from 2 farms.
~ Experimental trials to farm scallops (~~)and queens (~ opercularis) are in progress wi th most eff'Ort concentrated on methods of catching spat and also finding areas rich in spat0
USA
(A. Longwell and J. Ryther) I . The U.S. National Program in Aquaculture
The National Aquaculture Act of 1980 established a national policy to promote aquaculture in the United States. Although the National Sea Grant College Program has been supporting aquaculture research since 1968 this new act will provide considerable impetus to expand the scope of aquaculture activities. The current version of the National Aqua- culture Plan prepared by the Joint Subcornmittee on Aquaculture describes the present status and potential of aquaculture in the u.s., the barriers to its expansion, the actions that can be taken to reduce or eliminate these barriers and addresses the needs to promote the culture of some dozen aquaculture species.
The National Aquaculture Act of 1980, signed by the President on September 26, declared the development of aquaculture in the U.S. to be national policy and called for a coordinated program involving 13 Federal agencies and departmen'::s, The Secretaries of Agriculture, Cornmerce and lnterior are assigned primary responsibility for the conduct of the expanded R&D and related programs authorized in the Act. In a Memorandum of Understanding approved by the three Departments in April 1980, the Department of Commerce was assigned responsibility for aquaculture research and development on marine, estuarine and anadromous species. This re- search is to be conducted or funded by the National Marine Fisheries Service and the Office of Sea Grant (OSG) . In addition, OSG is to meet the education, training and advisory service needs of marine aquaculturists.
